Help! H370MiITX/AC always freezes in Windows

Hi,

I hope you can help me as I haven't had a great experience with the H370M-ITX/ac motherboard.

The system will randomly freeze when in Windows 10 Pro where the entire screen freezes, and then I restart the system by turning off and back on again from the power switch, and it won't even display POST. I can see the fans turning so there is power. I then have to wait some time before I turn it on again and it boots to POST and then Windows.

I've updated the bios to the latest version which is 4.30.

The system have the following:

Two 16GB Corsair 2133 RAM Modules
Samsung 860 EVO SATA M.2 500 GB
Intel i7 8700
Gigabyte GeForce PCIe
600W PSU

I've disabled the S3 Power Options, and also upped the DRAM to 1.25V.

Has anyone seen this before, and anything else I can try before needing to consider purchasing a new motherboard?

Thanks!

Should I consider underclocking it?

The thermals seem OK, and I also set all the fans to Performance Mode in the Bios.

My thermals are as follows:

CPU temp 38 degrees Celcius
Mb temp 47 degrees Celcius
CPU fan speed 2051 RPM

I upped the voltage based on another post in case it may have fixed it although this was for slightly different RAM as I was out of options.

Any ideas on what to try now?

Windows was installed on the SSD attached to this PC and I installed all of the drivers from the ASRock support page if that helps which had a specific version if the Intel drivers.

Windows is also the x64 edition as well.

I'll see if I can find out.

What I don't understand though is why it won't reboot back into Windows, and it won't even POST during the reboot process

Does that indicate a hardware failure with the motherboard?

I can also see that all of the CPU Cores temperature is at 70% now that I'm running Prime95 to perform a stress test on the computer.

The RAM is also 2 x 32GB Corsair DDR4-2066 and